By Peter Russell
WebMD Health News
Reviewed by Sheena Meredith, MD
April 17, 2015 -- Scientists say they've created a blood test that can predict whether a woman will get breast cancer several years before the disease shows up.
The technique, which involves measuring compounds in the blood, is still in its early stages. But in the long run it could help people with the disease get treated sooner, and help doctors show women at risk how to lower their odds of getting it.
Researchers at the University of Copenhagen in Denmark say the new test can predict breast cancer's onset 2 to 5 years in advance with 80% accuracy. That's compared to mammograms, which can spot the disease itself with 75% accuracy.
Details of the test have been published in the journal Metabolomics.
"The method is better than mammography, which can only be used when the disease has already occurred. It is not perfect, but it is truly amazing that we can predict breast cancer years into the future," says researcher Professor Rasmus Bro.
The research is based on a study of 57,053 men and women tracked by the Danish Cancer Society over 2 decades. The scientists used 20-year-old blood samples and other data from more than 400 women who were diagnosed with breast cancer 2 to 7 years after giving their first sample. These samples were compared with those from a group of an equal number of women who didn't get the disease.
The scientists then created a kind of profile for each person that they used to check for chemical changes that can happen before breast cancer tumors show up.
More trials are needed to refine the technique, but "the potential is that we can detect a disease like breast cancer much earlier than today. This is important, as it is easier to treat if you discover it early," says researcher Lars Ove Dragsted.
Still, even though the blood test can spot women with a higher risk, some of them may never get the disease, says Matthew Lam, PhD, senior research officer at Breakthrough Breast Cancer and Breast Cancer Campaign in the U.K.
If you're concerned about your risk, talk with your doctor, Lam says. "For some women, extra screening may be an option, as mammography remains the best tool we have to detect breast cancer at an early stage."
In 2015, about 231,000 U.S. women will be diagnosed with invasive breast cancer, the American Cancer Society estimates.
SOURCES: Bro, R. Metabolomics, April 2015. Press release, University of Copenhagen. Cancer Research UK. Breakthrough Breast Cancer and Breast Cancer Campaign. American Cancer Society.
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